1. Technical Field
The present invention relates to a printed circuit board, more particularly to a printed circuit board having an embedded electronic component and manufacturing method thereof.
2. Description of the Related Art
As a part of next-generation multi-functional miniature package technology, attention is being focused on the development of a printed circuit board having embedded electronic components. Along with the advantages of multi-functionality and miniaturization, a printed circuit board having embedded electronic components also allows, to a degree, more sophisticated functionalities, as the wiring distance can be minimized in a high-frequency range of 100 MHz or higher, and in some cases, problems in reliability may be resolved for connections between components using wire bonding or solder balls in an FC (flexible circuit board) or a BGA (ball grid array).
However, in a conventional printed circuit board having embedded electronic components, there is a high probability that problems in heat release due to embedding electronic components such as high-density IC's, or problems such as delamination, etc., will affect the yield, and there are difficulties in the overall process that raise the costs of manufacture. Therefore, a technology is required which provides stiffness for minimizing warpage in thin printed circuit boards, and which provides improvements in heat-releasing property.
Examples of prior art related to the printed circuit board having embedded electronic components include, first, a method of utilizing tape and a molding compound for embedding the electronic components. In this invention, liquid epoxy material is utilized in embedding the components after etching an insulation substrate, so as to minimize the thermal and mechanical impact caused by differences in the coefficients of thermal expansion and the coefficients of elasticity between the embedded electronic component, such as IC's, and the substrate. However, it is limited in that the stiffness and heat-releasing property of the substrate itself are unchanged.
A second example includes an invention of using a metal substrate for a core member of the printed circuit board and forming resin layers as insulation layers, to improve the mechanical and thermal properties of the board. However, this invention is not of a structure that enables embedding electronic components in the core member, and the problem of delamination remains a possibility.
A third example includes an invention in which a metal substrate is used as a core member, with an insulation layer on one side of the metal substrate and an electronic component embedded in the insulation layer. However, this invention is not of a structure that enables embedding electronic components in the core member, so that the thickness of the printed circuit board is increased by the thickness of the insulation layer necessary for embedding electronic components.